Auth::attempt always return false

Hello everybody, I'm kind a newbie on Laravel and start learning L 5 form the beggining.

Sure that I'm doing a really really noob error, but I don't figure out.

Well, I'm trying to make a custom login, but, the Auth::attempt() always return false. Here's my code.

Config\auth.php

<?php

return [

    'driver' => 'eloquent',

    'model' => 'App\User',

    'table' => 'usuarios',

    'password' => [
        'email' => 'emails.password',
        'table' => 'password_resets',
        'expire' => 60,
    ],

];

Migration & Seed

<?php

use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateUsersTable extends Migration {

    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('usuarios', function(Blueprint $table)
        {
            $table->increments('usu_id');
            $table->string('usu_nome')->unique();
            $table->string('usu_senha', 60);
            $table->integer('clu_id');
            $table->rememberToken();
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::drop('usuarios');
    }

}

<?php

use Illuminate\Database\Seeder;
use Illuminate\Database\Eloquent\Model;
use App\User as User; // to use Eloquent Model 

use Illuminate\Support\Facades\Hash;

class DatabaseSeeder extends Seeder {

    /**
     * Run the database seeds.
     *
     * @return void
     */
    public function run()
    {
        Model::unguard();

        $this->call('UserTableSeeder');
    }

}

class UserTableSeeder extends Seeder {
    public function run() {
        // add 1st row
        User::create(['usu_nome' => 'UsuTeste', 'usu_senha' => Hash::make('123456')]);
    }
}

My Model in App\User.php

<?php namespace App;

use Illuminate\Auth\Authenticatable;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Auth\Passwords\CanResetPassword;
use Illuminate\Contracts\Auth\Authenticatable as AuthenticatableContract;
use Illuminate\Contracts\Auth\CanResetPassword as CanResetPasswordContract;

class User extends Model implements AuthenticatableContract, CanResetPasswordContract {

    use Authenticatable, CanResetPassword;

    /**
     * The database table used by the model.
     *
     * @var string
     */
    protected $table = 'usuarios';
    protected $primaryKey = 'usu_id';

    /**
     * The attributes that are mass assignable.
     *
     * @var array
     */
    protected $fillable = ['usu_nome', 'usu_senha'];

    /**
     * The attributes excluded from the model's JSON form.
     *
     * @var array
     */
    protected $hidden = ['usu_senha', 'remember_token'];

}

And finally, my custom auth controller

<?php namespace App\Http\Controllers;

use Auth;
use Illuminate\Routing\Controller;
use Illuminate\Http\Request;

use Illuminate\Support\Facades\Hash;

class AuthController extends Controller {

    public function getLogin(){
        return view('auth.login');
    }

    /**
     * Handle an authentication attempt.
     *
     * @return Response
     */
    public function authenticate(Request $request){
        $credentials = array('usu_nome' => $request->usu_nome, 'usu_senha' => $request->usu_senha);

        if (Auth::attempt($credentials, false)){
            dd('success');
            return redirect()->intended('dashboard');
        }else{
            dd('failed');
        }
    }
}